High stability quartz crystal resonators that can consistently withstand extremely high shocks, such as occur during launch from a howitzer, have not been available previously.
In the past, efforts have been made to prepare quartz resonators that can withstand extremely high shocks by electroplating a nickel rim onto a quartz blank to provide both strength and a non-contaminating bond to the support structure. Although the nickel electrobonding process can permit resonators to survive very high shock levels, the process is difficult to implement and control. Such a nickel electrobonding process is described in the article "Further Results on UV Cleaning and Ni Electrobonding" by J. R. Vig, J. W. LeBus, and R. L. Filler at pages 220 to 229 of the Proceedings of the 29th Annual Symposium on Frequency Control, 1975. The high shock aspect of the nickel electrobonding process is further discussed in the article "The Effect of Bonding On the Frequency vs. Temperature Characteristics of AT-Cut Resonators" by R. L. Filler and J. R. Vig at pages 264 to 268 of the Proceedings of the 30th Annual Symposium On Frequency Control, 1976.